Most of the top hotel concierge services in Tokyo can easily book this shop, too. If you are staying at a 5 star hotel and they are telling you they cannot secure a reservation at Takamitsu, I'd recommend moving to a different hotel.
They are completely different. Miyoshi focused more on expensive over the top ingredients & theatrical effect while Jo offered more variety of dishes showing the culinary skill of the chef, in additional to ingredient sourcing skill. Jo is a smaller restaurant with wooden counter. It’s a simple yet elegant restaurant so the vibe at both places is completely different too. By the way, there’s one gentleman in their board wrote his comment on Miyoshi on this board too.
Sorry for the late reply but I think that they only accept reservations via facebook from Japanese customers . I actually gave the contact of one of my friends in Japan instead of my own information. (+ I wrote to them in Japanese). They must've thought I was Japanese haha. Maybe next time you should try that instead.
Below are the prices and the cancellation charges quoted by my hotel for satake when I went for lunch early this month(Aug 2018).
Restaurant: Sushi Satake
Course: 12,960JPY per person course only
Cancellation policy: 100% of te course if you cancel the reservation on the reservation day.